Printing mechanism actuator

ABSTRACT

A printing mechanism actuator for use with a hammer assembly in an on-the-fly type digital printer. The actuator is magnetically actuated and through an actuating arm imparts force to a corresponding hammer pin to cause it to be thrust into printing position. Support structure aligns the actuating arm, and spring biasing means connected to the support effectively returns the actuating arm to its resting position after actuation. The actuators are placed so that each succeeding actuator opposes the preceding actuator with only the hammer impact areas forming a common line and this design coupled with the compactness of the actuators permits the placement of ten units per lineal inch.

United States Patent 91 [111 3,745,497 Cavella [451 July 10,1973

[ PRINTING MECHANISM ACTUATOR V [75] Inventor: James J. Cavella, Philadelphia, Pa.

[7 3] Assignee: Datadyne Corporation, King of Prussia, Pa.

[22] Filed: Aug. 11, 1971 [21] Appl. No.: 170,734

[52] US. Cl. 335/266, 101/93 C [51] Int. Cl. 1101! 7/08 [58] Field of Search 101/93 C; 335/266, 335/268 [56] References Cited UNITED STATES PATENTS 3,636,868 1/1972 Johnston etal 101/93 C 3,195,453 7/1965 Thiemann 335/266 X 3,349,696 10/1967 Potter 101/93 C Primary Examiner-George Harris Attorney-Woodcock, Washburn, Jurtz & Mackiewicz [57] ABSTRACT V actuating arm to its resting position after actuation.

The actuators are placed so that each succeeding actuator opposes the preceding actuator with only the hammer impact areas forming a common line and this design coupled with the compactness of the actuators permits the placement of ten units per lineal inch.

3 Claims, 3 Drawing Figures 1 PRINTING MECHANISM ACTUATOR BACKGROUND OF THE INVENTION 1. Field of the Invention SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a printingmechanism actuator for use in con- This invention relates to a printing mechanism actua- 5 junction with a hammer assembly whereby the requiretor that has utility when used in conjunction with a print hammer assembly for a digital printer of the onthe-fly type. The actuators so designed may be used with a hammer assembly such as is disclosed in my copending application Ser. No. 153,685, entitled Digital Printer Hammer Assembly filed June 16, 1971. The hammers as disclosed in the above application are aligned in a continuous row along the length of a hammer block assembly and in position to strike characters on a moving print drum when actuated by the individual actuators of the actuator assembly. Capability of printing at a density of ten characters per lineal inch is necessary requiring that the individual actuators, as well as, the individual hammers must be of a very compact design.

2. Prior Art Various printer formats have been used in the past to achieve a placement where the hammers and actuators correspond to a line of printed characters with a linear pitch of 0.1 inch. An inherent difficulty lies in placing the actuators which must be designed to meet the requisite power demands in close proximity yet preventing interference between succeeding actuators.

One format that has been used is to fan out placement of the actuators in radial fashion so that only their impact tips are on 0.1 inch centers. A disadvantage of this format is that after a certain number of actuators are placed the final end actuators are at 90 to the hammer block. This limits the printer in the number of columns that may be used.

Another format has been to build the actuators in three or four unit modules and to rotate them around the hammer block so that the magnetic fields do not interfere. In this format, individual actuators per module are on 0.3 inch or 0.4 inch centers. Several disadvantages are present with this construction. First, a printer must be built with a number of columns which is an exact multiple of the number of actuators in a module. Another disadvantage is that intricate mounting schemes must be employed involving a need to use actuators of different design so that neighboring actuators are not interfered with.

In US. Pat. No. 3,468,246 issued Sept. 23, 1969 to R. H. Lee et al., hammers with self-contained electromagnetic actuating means are disclosed as placed in line fashion with the actuators on opposing sides so that only the hammer impact areas form a common line. In such a design, however, the bulkiness of the actuators makes it. extremely difficult to meet the size' standard required for the placement of centers at 0.1 inches. Also complex channeling is necessary for mounting the actuators in a design such as this.

A requirement that is manifest in the placing of actuators in such close proximity is the absolute necessity to have the actuators maintained in perfect alignment. US. Pat. No. 3,195,453 issued July 20, 1965 to F. V. Thiemann discloses a print hammer where the magnet is external to the pivot point of the actuator arm. A problem with this type of structure is the lack of consistency of relationship between the lever arm and magnet which creates an alignment problem.

ments for a line of printed characters having a linear pitch of 0.1 inches is met.

It is another object of the present invention to provide a printing mechanism actuator so designed that a,

bank of actuators may be placed on one side of a hammer block and another bank may be placed on the other side of the block to permit close spacing of hammer impact areas.

It is yet another object of the present invention to provide a printing mechanism actuator which is designed so that actuators can be placed in a lineal fashion.

It is still another object of the present invention to provide a printing mechanism actuator in which the number of actuators need not be a multiple of a given number.

It is a further object of the present invention to provide a printing mechanism actuator assembly where each actuator is identical to the others and may be easily replaced or repaired. i

It is a still further object of the present invention to provide a printing mechanism actuator which can be manufactured at relatively low cost.

It is yet a further object of the present invention to provide a printing mechanism actuator which may be easily installed on any flat surface.

In accordance with the object of the invention a printing mechanism actuator is provided where a single support member is provided which furnishes the base for the electromagnetic energizing means, acts as the pivotal connecting means and the guiding means for an actuating arm, and further has attached to it spring means for returning the actuating arm to its resting position after actuation. The actuating arm which is pivotally mounted onto the supportis kept in alignment by a channelized portion of the support. The printing actuating arm has an armature attached to a portion of the arm which extends over upright members .extending upwardly from the base of a portion of the support, the upright members having windings for magnetizing them with opposite polarity at their outwardly extending ends.

The actuators are so designed so that one bank may be placed on one side of a hammer block assembly having multiple individual hammers and the other bank positioned on the other side of the hammer block thus allowing 0.1 inch center placement at the hammer impact areas although each succeeding hammer actuator of the same bank is placed at 0.2 inches linearly..

Other features and advantages of the present invention will be apparent from the preferred embodiment hereinafter set forth and illustrated in the accompanying drawings.

BRIEF DESCRIPT ION OF THE DRAWINGS FIG. 1 is a front view showing the printing mechanism actuators as part of a line printer;

FIG. 2 is a front elevation view of a printing mechanism actuator; and

FIG. 3 is a perspective viewing showing more detail of a printing mechanism actuator.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1 an on-the-fly drum type line printer is shown having a hammer block assembly positioned adjacent a drum 12 which has print characters (not shown). An inked ribbon 14 extending through ribbon assembly 15 and paper 16 feeding from roll 17 along table assembly shown generally by 19 are guided between the hammer block assembly 10 and the print drum 12. Multiple hammer actuating means which are designated generally by reference numeral 18, are placed in contacting relationship to the hammer pins 20 of the hammer block assembly 10.

Referring to FIG. 2, each individual actuator 18 has a support member 30 which is generally of a U-shape configuration having a base 32 and side sections 34 and 35. Side section 34 is bifurcated to form channel 36 (FIG. 3) having portions 37 and 39 to receive an actuating arm 38. The bifurcated portions 37 and 39 extend along the actuating arm for a distance past the side support section 34 and forwardly toward the impact area. These extensions 41 and 43 assist in keeping the actuating arm 38 aligned. The actuating arm 38 has a rear portion 40 and a front portion 42, the front portion having raised areas 44 and 46. As can be seen from FIG. I, raised area 44 is aligned to impact against hammers 20 while raised portion 46 rests upon the module block 48 when the actuator is in the rest position.

Actuating arm 38 pivots about pivot means 50 comprising a pin or other suitable means and which is secured to the support member 30 in side 34. The rear portion 40 of the actuating arm 38 has attached thereto an armature 52 of magnetic material. Positioned below the armature 52 are two upright members 54 and-'56 extending upwardly from the base 32 of the support member 30. Windings 58 and 60 are wrapped around upright members 54 and 56 for the purpose of magnetizing the upright members 54 and 56 with opposite polarity at their upwardly extending end. Energy is applied to windings 58 and 60 through terminals 62 and '64 positioned on side 35 of support member 30. Spring member 66 extends from the actuating arm 38 to the support member 30. One end of the spring 66 hooks into an aperture 70 in actuating arm 38 and the other end of the spring 66 grasps extension 72 in a grooved portion (not shown) of the extension 72 so as to firmly hold spring 66 in place.

Tape (not shown) or other suitable means may be wrapped around windings 58 and 60 to protect the windings and prevent influence from adjoining members.

Thus when energy is applied to windings 58 and 60 the magnetic armature 52 ill be attracted downwardly causing the raised area 44 to thrust the corresponding hammer pin 20 upwardly to its printing position. At the completion of the energy pulse, the magnetic attraction will cease and a portion 42 of the actuating arm 38 ill drop downwardly as aided by spring member 66 to a point where raised area 46 rests upon block assembly 48 the height of which is accurately determined.

The relationship of the actuating arm 38 and the support 30 and of the positioning of the spring 66 and pivot means 50 are to be noted. The support 30 which also integrally provides a base 32 for winding members 54, 56 and a member 35 for terminals 62, 64 provides not only an extended channel 36 to keep arm 38 in alignment, but also provides the support for both the pivot means 50 and spring holder 72. Since pivot means 50, channel 56, spring members 66 and windings 54, 56 which influence the armature 52 of arm 38 are all consistently and fixedly disposed to one another the constant alignment of arm 38 is insured.

As can be seen in FIG. ll, each succeeding actuator is placed on the opposite side of the block assembly with only the impact points 44 and 46 being placed in a common line corresponding to the line of hammer pins 20 along the length of the printing surface. In this manner, although the individual actuators are placed on 0.2 inch centers, the effective impact areas are reduced to 0.1 inches. Interference problems with succeeding actuators are thus minimized and the tape wrapping around the individual windings 56 and 58 of the actuators further minimizes interference between them. Each actuator is secured firmly in place by screws (not shown) which secure the base of the support 30 in several mounting holes (not shown) apart from one another to the printer base member 74 or other flat positioning plate. With the supports 30 firmly placed, each actuating arm 38 is precisely positioned and operates in continual alignmentbecause of the consistency of relationships as previously described.

While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that changes in form and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. An actuator for a printing mechanism comprising:

an integral support member having an elevated bifurcated portion which forms a channel, and a base portion adjacent thereto having two thin upright members,

a non-magnetized printing actuating arm disposed within said channel and pivotally secured in said channel, the actuating arm being guided for pivotal movement by said channel and having a length extending outwardly across the upright members of said support member, said channel being longitudinally coextensive with a portion of said actuating arm,

windings on each of said upright members for magnetizing said upright members'with opposite polarity at their upwardly extending ends,

an armature secured on the length of the actuating arm which extends outwardly across the uprights, and

a spring member extending from said actuating arm to a portion of said support member to cause said printing actuating arm, with its armature, to be in spaced relation with said upright members in a rest position whereby upon energization said printing actuating arm is pivoted into printing position, said spring member being attached to said actuating arm at a position where said actuating arm is longitween centers with their printing actuating arms being selectively actuated by selective energization of said windings.

Yntcnt No. 3 97 Dated July 10, 1973 C I Invcntor(s) James J. Cavella It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

r Title Page, deiete "Jurtz" and insert "Kurtz" Column 3, line 23, delete "These" and insert "The" 'line 40,- delete- "end" and insert "ends"; 'line 58, after "a" insert "forward"; line 58, delete "ill" and insert "will" line 64, delete "which also" I line 65, after "provides." insert "the following"; line 66, delete "and" and insert line 66, after "a" insert "support" line 67 delete "provides not" line 68, delete "only" and. insert ,Column 4, "line 1, delete but also provides the" line l,delete "both"; line 2, after "50" insert line 2, after "and" insert "support for" line 2, after 72" insert "whereby the. spring 66 is attached to the actuating arm below support extensions 41 and 43 as shown in'Fig. 2"; line 6, delete "insured" and insert, "ensured"; line 7, after "actuator" insert ."18" jline 1.8, arter "actuator insert "18" line 19, delete the second "the" and insert "each" 1. line 20, delete "apart" line 21,- delete "from one another to" and insert "in" Signed and sealed this 20th day of August 197A.

(SEAL) Attest:

McCOY M. GIBSON, JR. MARSHALL DANN Attesting Officer I Commissioner of Patents Patent No. ,745,497

Inventor) James J. Cavella UNmcp S'IA'Il'ZS lA'll'lN'l OFFICE CER'LUFICA'IFE OI." (JOR'REC'IION Dated J l 10, 1973 It is certified that error appears in the above-identified patent: and that said Letters Patent are hereby corrected as shown below:

,Column 4,"

"Jurtz and insert "Kurtz". delete "These" and insert "The";

delete "end" and insert "ends";

after "a" insert "forward";

delete "ill" and insert "will";

delete "which also" after "provides." insert "the following"; delete "and" and insert after "a" insert "support" delete "provides not" delete "only" and insert delete but also provides the" l,delete "both";

after "50" insert 7 after 'and" insert "support for". after "72", insert whereby the.

spring 66 is attached to the actuating arm below support extensions 41 and 43 as shown iIf'Fig. 2";

line 6, delete "insured" and insert,"ensured"; f line 7, after "actuator" insertr"l8"; line l8, arter "actuator insert "l8";

J line 19, delete the second "the" and insert "each line 20, delete "apart" I i line 21, delete "from one another to" and insert "in" Signed and sealed this 20th (SEAL) Attest:

MCCOY M. GIBSON, JR. Attesting Officer day of Au gust 19 7A.

C. MARSHALL DANN Commissioner of Patents 

1. An actuator for a printing mechanism comprising: an integral support member having an elevated bifurcated portion which forms a channel, and a base portion adjacent thereto having two thin upright members, a non-magnetized printing actuating arm disposed within said channel and pivotally secured in said channel, the actuating arm being guided for pivotal movement by said channel and having a length extending outwardly across the upright members of said support member, said channel being longitudinally coextensive with a portion of said actuating arm, windings on each of said upright members for magnetizing said upright members with opposite polarity at their upwardly extending ends, an armature secured on the length of the actuating arm which extends outwardly across the uprights, and a spring member extending from said actuating arm to a portion of said support member to cause said printing actuating arm, with its armature, to be in spaced relation with said upright members in a rest position whereby upon energization said printing actuating arm is pivoted into printing position, said spring member being attached to said actuating arm at a position where said actuating arm is longitudinally within said channel thus providing for consistent and fixed disposition of the spring means, the windings, and the pivotal connection of said actuating arm, and in conjunction with said channel, to provide constant alignment of said actuator.
 2. The actuator of claim 1 wherein said channel of said support member coextends with said actuating arm for approximately one third of the length of said actuating arm.
 3. The printing actuator of claim 1 in which means are provided to mount plural actuators in opposite rows to provide spacings of the order of one-tenth inch between centers with their printing actuating arms being selectively actuated by selective energization of said windings. 